Is there a way to make a vertical grid show on final image rendered?
One way to "make one yourself" as @gandalf3 said above is this:

add a plane  subdivided as you "scale", and use a material as "grid" and "shadeless".

it will look like this (blender render)



here I used 2 planes, you may tweak the grid appearance...
is this something similar to what you need? 

for "cycles render"
you can try a "wireframe" modifier, and a suited material, like 



but probably, a freestyle setup would fit both cases... I'll add that later, or others will suggest howto here...

[edit] Yes freestyle would work with both cycles and internal render:


activate the master freestyle flag in the render option tab
set a freestyle linestyle in the render layers option tab, with the color/style you prefer, and enable as edge types only "edge mark" for it
mark all subdivided grid mesh edges as "freestyle edge"
set the material of the grid to be completely transparent (different in cycles and internal, anyway remove all reflection, specular, shinyness)


like this:



results in cycles and internal can be quite similar (for the grid):




and, finally, I tried and even the wireframe modifier works in cycles and internal, only a the grid material must be defined differently (eg: white shadeless for internal, white emission for cycles).

freestyle can give you much more choice of linestyle (eg: dotted, hand drawn, etc), but the setup is slightly more complex, and since is a post-render effect, it could interfere with some of the scene setup to render as you wish, depending on the scene.